Wave-5 refinement round 3 (owner): SVG answer marks + uniform input sizes

- ✓/✗ in the answered card: replaced literal glyphs with lucide CheckIcon/
  XIcon (strokeWidth 2.5) inside a fixed size-4 flex box — text elements
  never carried the right size/vertical alignment, vectors do. Test pins
  updated (lucide-check/lucide-x classes).
- All user-typed INPUT text now matches markdown output: lh-prose class
  replaces the earlier font-prose (family-only) band-aid on the composer,
  question-dock text/thinking/Other fields, home topic input, model search
  box, and answered-card 'your thinking'/free-text records. lh-prose sets
  family+size (16.5px) so placeholders inherit correctly.

components/model-picker.tsx

@@ -198,7 +198,7 @@ export function ModelControl({
 						value={query}
 						onChange={(e) => setQuery(e.target.value)}
 						placeholder="Search models…"
-						className="mb-1.5 w-full rounded-lg border bg-background px-2 py-1.5 text-foreground outline-none focus:ring-1 focus:ring-ring"
+						className="lh-prose mb-1.5 w-full rounded-lg border bg-background px-2 py-1.5 text-foreground outline-none focus:ring-1 focus:ring-ring"
 					/>
 					{error && <div className="mb-1.5 text-destructive">{error}</div>}
 					{!catalog && (